OpenCloudOS-Kernel/arch/blackfin/mach-bf548/gpio.c

324 lines
7.6 KiB
C

/*
* File: arch/blackfin/mach-bf548/gpio.c
* Based on:
* Author: Michael Hennerich (hennerich@blackfin.uclinux.org)
*
* Created:
* Description: GPIO Abstraction Layer
*
* Modified:
* Copyright 2007 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/module.h>
#include <linux/err.h>
#include <asm/blackfin.h>
#include <asm/gpio.h>
#include <asm/portmux.h>
#include <linux/irq.h>
static struct gpio_port_t *gpio_array[gpio_bank(MAX_BLACKFIN_GPIOS)] = {
(struct gpio_port_t *)PORTA_FER,
(struct gpio_port_t *)PORTB_FER,
(struct gpio_port_t *)PORTC_FER,
(struct gpio_port_t *)PORTD_FER,
(struct gpio_port_t *)PORTE_FER,
(struct gpio_port_t *)PORTF_FER,
(struct gpio_port_t *)PORTG_FER,
(struct gpio_port_t *)PORTH_FER,
(struct gpio_port_t *)PORTI_FER,
(struct gpio_port_t *)PORTJ_FER,
};
static unsigned short reserved_gpio_map[gpio_bank(MAX_BLACKFIN_GPIOS)];
static unsigned short reserved_peri_map[gpio_bank(MAX_BLACKFIN_GPIOS)];
inline int check_gpio(unsigned short gpio)
{
if (gpio == GPIO_PB15 || gpio == GPIO_PC14 || gpio == GPIO_PC15
|| gpio == GPIO_PH14 || gpio == GPIO_PH15
|| gpio == GPIO_PJ14 || gpio == GPIO_PJ15
|| gpio > MAX_BLACKFIN_GPIOS)
return -EINVAL;
return 0;
}
inline void portmux_setup(unsigned short portno, unsigned short function)
{
u32 pmux;
pmux = gpio_array[gpio_bank(portno)]->port_mux;
pmux &= ~(0x3 << (2 * gpio_sub_n(portno)));
pmux |= (function & 0x3) << (2 * gpio_sub_n(portno));
gpio_array[gpio_bank(portno)]->port_mux = pmux;
}
inline u16 get_portmux(unsigned short portno)
{
u32 pmux;
pmux = gpio_array[gpio_bank(portno)]->port_mux;
return (pmux >> (2 * gpio_sub_n(portno)) & 0x3);
}
static void port_setup(unsigned short gpio, unsigned short usage)
{
if (usage == GPIO_USAGE) {
if (gpio_array[gpio_bank(gpio)]->port_fer & gpio_bit(gpio))
printk(KERN_WARNING
"bfin-gpio: Possible Conflict with Peripheral "
"usage and GPIO %d detected!\n", gpio);
gpio_array[gpio_bank(gpio)]->port_fer &= ~gpio_bit(gpio);
} else
gpio_array[gpio_bank(gpio)]->port_fer |= gpio_bit(gpio);
SSYNC();
}
static int __init bfin_gpio_init(void)
{
printk(KERN_INFO "Blackfin GPIO Controller\n");
return 0;
}
arch_initcall(bfin_gpio_init);
int peripheral_request(unsigned short per, const char *label)
{
unsigned long flags;
unsigned short ident = P_IDENT(per);
if (!(per & P_DEFINED))
return -ENODEV;
if (check_gpio(ident) < 0)
return -EINVAL;
local_irq_save(flags);
if (unlikely(reserved_gpio_map[gpio_bank(ident)] & gpio_bit(ident))) {
printk(KERN_ERR
"%s: Peripheral %d is already reserved as GPIO!\n",
__FUNCTION__, per);
dump_stack();
local_irq_restore(flags);
return -EBUSY;
}
if (unlikely(reserved_peri_map[gpio_bank(ident)] & gpio_bit(ident))) {
u16 funct = get_portmux(ident);
if (!((per & P_MAYSHARE) && (funct == P_FUNCT2MUX(per)))) {
printk(KERN_ERR
"%s: Peripheral %d is already reserved!\n",
__FUNCTION__, per);
dump_stack();
local_irq_restore(flags);
return -EBUSY;
}
}
reserved_peri_map[gpio_bank(ident)] |= gpio_bit(ident);
portmux_setup(ident, P_FUNCT2MUX(per));
port_setup(ident, PERIPHERAL_USAGE);
local_irq_restore(flags);
return 0;
}
EXPORT_SYMBOL(peripheral_request);
int peripheral_request_list(unsigned short per[], const char *label)
{
u16 cnt;
int ret;
for (cnt = 0; per[cnt] != 0; cnt++) {
ret = peripheral_request(per[cnt], label);
if (ret < 0)
return ret;
}
return 0;
}
EXPORT_SYMBOL(peripheral_request_list);
void peripheral_free(unsigned short per)
{
unsigned long flags;
unsigned short ident = P_IDENT(per);
if (!(per & P_DEFINED))
return;
if (check_gpio(ident) < 0)
return;
local_irq_save(flags);
if (unlikely(!(reserved_peri_map[gpio_bank(ident)] & gpio_bit(ident)))) {
printk(KERN_ERR "bfin-gpio: Peripheral %d wasn't reserved!\n", per);
dump_stack();
local_irq_restore(flags);
return;
}
if (!(per & P_MAYSHARE)) {
port_setup(ident, GPIO_USAGE);
}
reserved_peri_map[gpio_bank(ident)] &= ~gpio_bit(ident);
local_irq_restore(flags);
}
EXPORT_SYMBOL(peripheral_free);
void peripheral_free_list(unsigned short per[])
{
u16 cnt;
for (cnt = 0; per[cnt] != 0; cnt++) {
peripheral_free(per[cnt]);
}
}
EXPORT_SYMBOL(peripheral_free_list);
/***********************************************************
*
* FUNCTIONS: Blackfin GPIO Driver
*
* INPUTS/OUTPUTS:
* gpio - GPIO Number between 0 and MAX_BLACKFIN_GPIOS
*
*
* DESCRIPTION: Blackfin GPIO Driver API
*
* CAUTION:
*************************************************************
* MODIFICATION HISTORY :
**************************************************************/
int gpio_request(unsigned short gpio, const char *label)
{
unsigned long flags;
if (check_gpio(gpio) < 0)
return -EINVAL;
local_irq_save(flags);
if (unlikely(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio))) {
printk(KERN_ERR "bfin-gpio: GPIO %d is already reserved!\n", gpio);
dump_stack();
local_irq_restore(flags);
return -EBUSY;
}
if (unlikely(reserved_peri_map[gpio_bank(gpio)] & gpio_bit(gpio))) {
printk(KERN_ERR
"bfin-gpio: GPIO %d is already reserved as Peripheral!\n", gpio);
dump_stack();
local_irq_restore(flags);
return -EBUSY;
}
reserved_gpio_map[gpio_bank(gpio)] |= gpio_bit(gpio);
local_irq_restore(flags);
port_setup(gpio, GPIO_USAGE);
return 0;
}
EXPORT_SYMBOL(gpio_request);
void gpio_free(unsigned short gpio)
{
unsigned long flags;
if (check_gpio(gpio) < 0)
return;
local_irq_save(flags);
if (unlikely(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio)))) {
printk(KERN_ERR "bfin-gpio: GPIO %d wasn't reserved!\n", gpio);
dump_stack();
local_irq_restore(flags);
return;
}
reserved_gpio_map[gpio_bank(gpio)] &= ~gpio_bit(gpio);
local_irq_restore(flags);
}
EXPORT_SYMBOL(gpio_free);
void gpio_direction_input(unsigned short gpio)
{
unsigned long flags;
BUG_ON(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio)));
local_irq_save(flags);
gpio_array[gpio_bank(gpio)]->port_dir_clear = gpio_bit(gpio);
gpio_array[gpio_bank(gpio)]->port_inen |= gpio_bit(gpio);
local_irq_restore(flags);
}
EXPORT_SYMBOL(gpio_direction_input);
void gpio_direction_output(unsigned short gpio)
{
unsigned long flags;
BUG_ON(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio)));
local_irq_save(flags);
gpio_array[gpio_bank(gpio)]->port_inen &= ~gpio_bit(gpio);
gpio_array[gpio_bank(gpio)]->port_dir_set = gpio_bit(gpio);
local_irq_restore(flags);
}
EXPORT_SYMBOL(gpio_direction_output);
void gpio_set_value(unsigned short gpio, unsigned short arg)
{
if (arg)
gpio_array[gpio_bank(gpio)]->port_set = gpio_bit(gpio);
else
gpio_array[gpio_bank(gpio)]->port_clear = gpio_bit(gpio);
}
EXPORT_SYMBOL(gpio_set_value);
unsigned short gpio_get_value(unsigned short gpio)
{
return (1 & (gpio_array[gpio_bank(gpio)]->port_data >> gpio_sub_n(gpio)));
}
EXPORT_SYMBOL(gpio_get_value);